CWD Unlikely to Spread in Moose

February 24, 2013

EDMONTON - Alberta officials say the discovery of one moose with chronic wasting disease doesn't mean the infection could spread through the province's entire population of the animals.

Moose can catch the disease, which is similar to mad cow disease, but aren't likely to pass it to other moose.

"There's no evidence that the disease can or will establish a sustaining nucleus of disease in moose," said Alberta Environment spokeswoman Nikki Booth. "They can get it, they just can't transmit it."

On Tuesday, wildlife officials announced that an adult bull moose that had been killed in a collision with a vehicle last November had been autopsied and diagnosed with chronic wasting disease. The Alberta government says it's the first discovery of CWD in a Canadian moose.

The disease has been present in low levels in Alberta deer for a decade. The sick moose was found near Medicine Hat in southern Alberta, in one of the areas where sick deer have been found.

Affected deer become emaciated and exhibit abnormal behaviours — such as excessive drooling, grinding of teeth and difficulty with orientation — before dying.

Moose, deer and elk are in the same biological family and scientists suspected Alberta moose could be vulnerable to diseases carried by their cervid cousins. There are previous examples of deer infecting moose with chronic wasting disease in Colorado and Wyoming, said Booth.

"CWD only occurs in moose when they overlap with infected deer. Our scientists knew that this could potentially happen and now they've found one."

University of Alberta biologist David Coltman said moose are temperamentally unsuited to be vectors of disease among their own kind.

"They're not likely to pass it from moose to moose just because of the way they live. They don't yard up the way deer do. They're quite territorial and solitary. They're ornery."

Coltman said the discovery of an infected moose probably says more about the rate of infection among deer.

"It is telling us that there are enough infected deer out there that it's possible we're going to start to seeing things like this."

While more infected moose are not expected, Booth said Alberta Environment continues to monitor the area for infected deer and will watch for more sick moose as well.

Government scientists are willing to test the heads of any moose that might be sick, said Booth.

The meat remains safe to eat. Scientists say the infectious parts of the carcass are restricted to the brains and material from the spinal column.

There have been no verified cases of people getting ill from infected deer, elk or moose.

Alberta has been trying to stem the flow of deer with chronic wasting disease coming in from Saskatchewan since 2005. The province once culled thousands of deer from herds along the boundary, but that program has ended.

Since last September, 23 cases of the disease have been diagnosed in deer out of nearly 3,000 specimens sent to the province for testing.